Which congenital abnormality of the gastrointestinal tract most characteristically has its clinical onset at 2 to 4 weeks of age and has a strong male preponderance?

Correct Answer: A

Rationale: The correct answer is A: pyloric stenosis. This condition typically presents at 2-4 weeks of age and is more common in males. The rationale behind this is that pyloric stenosis is the narrowing of the passage between the stomach and small intestine, leading to projectile vomiting after feeding, which becomes apparent around 2-4 weeks of age. Intestinal atresia, Meckel's diverticulum, and Hirschsprung's disease do not typically present with symptoms at this specific age range and do not have a strong male preponderance as seen in pyloric stenosis.

Correct Answer: C

Rationale: The correct answer is C: Low blood glucose is a feature after removal of the pancreas. The pancreas is an important organ that produces insulin to regulate blood glucose levels. After pancreas removal, insulin production is disrupted, leading to high blood glucose. This causes symptoms of hyperglycemia, not hypoglycemia. Choice A is incorrect as the pancreas is not an endocrine gland that secretes heparin; it is actually an endocrine gland that secretes insulin and glucagon. Choice B is also incorrect as high blood glucose, not low blood glucose, is a feature after pancreatic removal. Choice D is incorrect because only choice C is accurate.

Correct Answer: B

Rationale: Step 1: Bile is produced by the liver. Step 2: The liver synthesizes bile which is then stored and concentrated in the gallbladder. Step 3: When needed for digestion, bile is released from the gallbladder into the small intestine. Step 4: Therefore, the correct answer is B (Liver). Summary: - A (Gallbladder): Stores and concentrates bile but does not produce it. - C (Pancreas): Produces digestive enzymes and bicarbonate, not bile. - D (Hepatic Ducts): Carry bile from the liver to the gallbladder, do not produce bile.

Correct Answer: B

Rationale: The correct answer is B: Absorption of nutrients. The large intestine's main functions are absorption of water and formation of feces. Nutrient absorption primarily occurs in the small intestine, not the large intestine. Choice A is incorrect because the large intestine absorbs water to form solid waste. Choice C is incorrect because the large intestine is responsible for storing and eliminating feces. Choice D is incorrect as the large intestine does not absorb nutrients.

Correct Answer: D

Rationale: Step 1: Gastric juices contain hydrochloric acid, which helps in the breakdown of food and kills bacteria. Step 2: The combination of different enzymes in gastric juices works together to digest food effectively. Step 3: Therefore, the correct answer is D, as gastric juices in the stomach both kill bacteria and work together to digest food. Summary: - Choice A is incorrect because gastric juices do more than just killing bacteria. - Choice B is incorrect because gastric juices not only digest food but also kill bacteria. - Choice C is incorrect because gastric juices do more than just contain hydrochloric acid.